#include <stdio.h>

void printb(x,n)
int x,n;
{
    if(n > 0)
    {
        putchar('0'+((unsigned)(x&(1<<(n - 1)))>>(n - 1)));
        printb(x,n - 1);
    }
}

int main()
{
    int x;
    printf("Input number:");
    scanf("%d",&x);
    printf("number of decimal form: %d\n",x);
    printf("    it's binary form:");
    printb(x,sizeof(int) * 8);
    putchar('\n');
}